Fuse



- ff N 1,646,629@l Patented Det. 25, 1927.` i f,

- i UNITEDS'TATISA PATENT orare-12.3;

ELMEE. L. OGLE, lOE CHICAGO, ILLINOIS, AssIGNOR To FEDERAL ELECTRIC COMPANY,

OE CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS.` f 'l n FUSE.

Application med Noveriter'io, 1192s. sriarNo. 673,874.

This invention relates to improvements in electric fuses I and consists `of the matters hereinafterl described 'and more4 particularly pointed out in the appended claims.

vThe primaryobject of the invention isto improvethe construction of 'electric fuses which include a plurality of fusible `members, and lto so arrange and separate said members that each is located Vin an individual Compartment, so that when said members fuse or blow the arcs andthe pressures generated -thereby are each 'confined-l to `a is more quickly smothered orf extinguished, instead of being permittedV to combine with the other `fused members and produce such las will 'destroy the' usefulness of the casing or body of the fuse.v l Y Thejobject of the invention, Aas well as others, together withthe many advantages thereof will moreifully appear as 1 proceed y J ,with my speciication-v,l l

' VIn the drawings Fig. 1 is a vie-w in elevation of a fuse embodyingmy invention. Fig. 2 is a. view on an enlarged scale representing a longitudinal Vcentral section througlithe fuse.-

Fig. Sis ano-ther longitudinal central section' through lthe fuse as taken on the line 3-3 of Fig. 2. 7

Fig. 4 is a `cross-section through the Yfuse as taken on theline 4-'24 Of Fig. 2. i

Referring now to that embodiment of the invention illustrated in thedrawings 10 indicates the body ofthe fuse, which'is of the knife-blade Contact type, and 11, 12 indicate the conta-ctblades. 1 3 indicates asa whole the fusible member ofthe'fuse (see Fig. 1) which as shown inthis instance is contained in a renewable'cartridge 14.,` V,The fuse-body 10 is a heavy tube of Iinsulating material, such as fibre or theylikeandjis closed at itsends by metallic, tubularvhea'ds 15, 16, which carry thebladesll and 12 re` spectively. A

The head 16 is permanently attached to the tube 10. The tubular part of the head closely embraces the end of the fuse body 10 with its end wall engaged against a flat metal disc 17, which in turn engages against the end of the tubular body 10 and said head is fixed on the tube, preferably by means of rivets 18. The blade 12 extends through a slot in the fiat end wall of the head and has a high pressure spaced extensions 121, 12@ (see Fig.V @which proJectthrough holes in the disc 17` andare upset against the inner face of said disc'.

The other head 15 is made in two separablel parts, (see Figs. 2. and 3) namely, a short tube 19, which is permanently attached to the fuse body 10 by rivets 18?, and inner and outer flat .discs 20, A21V respectively. Said., discs are attached together and are secured to the associated blade 11by rneansfof spaced extensions 11a, 11'a onsaid blade,`

which are upset `against the inner face'rof.

the disc 20. Both of said discs'fit snugly within the open end of the metal tube 19 and. against the end of the fibre tube 10, beyond which said met-al tube extends a, distance equal to thethickness of the two discs.A The outer disc 21 has diametrically vOpposed ears4 22, 22 which extend at right angles to the plane of the disc and embrace the tube 19y and are secured thereto by screws 22,-the metal of the tube being 11p-set through the fibre tube 10 and tapped to receivef said screws. From the foregoing, it is apparent that `the removablepart of the fuse head 15 comprising the discs 20. and v21' and the 4connected blade 11, is readily removable for the purpose of replacing a fused or blown cartridge, and that it is. thereafter easily and quickly applied with its 'blade 11 always in the required plane..v f

The cartridge 111 has a tubular body oifin-` sulating material which is closed at itszends in any suitable manner. .f Y. y J

The fusible member 13 comprises as shown herein, two metal plugs 25, 26 which const-lby metal tubular caps 23, 24 secured thereto ltute terminals, one connected to each metal cap of the cartridge and ofa plurality of i fusible bars 27, `28 vand 29respectively,.con nected` to and supported by said plugs. .As

many fusible bars may be used as .arerem quired to carry the load.; Theplugs 25,26

are made ycylindrical as shown, and are profV 1 vided i'nitheir proiiimate ends with diametric slots 30, to: receive the ends` of the fusible bars Vwhich are secured thereto by rivets 31. The bars 27, 28 and 29 are arranged in parallel planes with their ends in juxtaposition and engaged in the slots 30 of the plugs 25 and 26 and with their4 intermediate lengths spaced apart as clearly illustrated in Fig. 2. Said bars are apertured between their ends to determine the effective crosssection in a familiar manner..

Between the fusible bars 27, 28 and 29 lv provide barriers 32, 32 of'heat resisting material in the form of flat sheets of mica of a lengthequal to the distance between the ends of the plugs 25, 26 and of a Width to engage y with substantially Vdiainetrically opposite points of the cartridge body. These barriers together With the proximate Walls of the cartridge body define arcing compartments, one for each fusible bar, so that when said bars fuse or blow their arcs are isolated from eachother and cannot combine to develo Y `a. gas pressure which would damage thel use as aWhole, and thus render it unfit for further use. As an example, assume that i' the Afuse is a 150 ampere fuse with each bar the reduced-end of the plug 25- next to the outer face of the cap 23 of the cartridge and n awasher 36, next to the plate 35, and all parts are secured to the plug and to each other by solder. The plate 35 is adapted to extend diainetr'ically acrossthecap 23 and beyondzit so that itslapertured end 35 cousti'tuting the tell-tale-tag may be bent down against the vmetal tube` I9 on the fuse body in advance of the application of the removable head.

After the fusible bars have beeifinserted inthe cartridge body, said body is loaded with the usual pulverulent material and a Wad of asbestosfbr'e is placed in each end of the cartridge; the said pulverulent material assisting in holding the barriers 32, 32 in a position parallel With and midwaybetween the fusible bars. In the adjacent heads of the cartridge and fuse body are provided vent holes throughfwhich the'gas escapes when the fuse blows, to relieve thepressure generated thereby. The cartridge is now ready for insertion into the fuse body and its capacity is shown on the tell-tale-tag v351.

To Aloadv the fuse With a 4cartridge,-the

cartridge is inserted in the fuse body and is then rotated until the threaded recess in the plug 26 may be engaged by the screw '34 in tion that When a fuse embodying my invention blows, for any reason, the rapidly generated gases cannot combine their pressures,

because each fusible member is isolated or separated from the adjacentfusible member. Thus, Vtheiforce'of said rapidly generated gases is reduced to a minimum and nofdanger can result to the fuse body, and therefore, said body can be used a numberof times,'a new cartridge being inserted in the fuse body when needed.

`While -Ain describing one embodiment of my invention I have referred to certain details of construction and arrangement of parts, I do not Wish to be limited thereto except as may be pointed out in the appended claims.

I claim as my invention:

l. In an electric fuse, the combination of a fuse body having a contact member at each end, a cartridge body in said fuse body provided With metal caps, metal plugs connected to the metal caps of the cartridge, a plurality of parallel, spaced fusible bars in said Y cartridge bodysaid bars being formed to bring their ends into contactual engagement, saidy ends being fixed in said plugs, vand barriers of heat-resisting material interposed iu the spaces between said'bars and engaged` against saidcartridge body.

2. A cartridge for an electric fuse comprising an insulation tubular bodyprovided With metal caps, metal plugsl connected to the metal caps ofthe cartridge, a plurality of parallel, spaced fusible bars in said, cartridge body, said bars being formed to bringtheir ends' into contactual engagement, said ends being fixed in said plugs, and barriers of heat-resisting material interposed in .the

' spaces between said bars and engaged against said` cartridge body.

In testimony .that I claim the foregoing as'my invention, I aliix my signature this 31st day of October, A. D. 1923.

` ELMER L. foGLE. 

